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Topological valley-locked waveguides with C4 impurity
Hongxiang Zhang1, Rensheng Xie2, Xiaofeng Tao3
1Key Laboratory of Polar Materials and Devices, Department of Electronic Sciences, School of Physics and Electronic Sciences, East China Normal University, Shanghai 200241, China.
Nanophotonics (Berlin, Germany)
|December 5, 2024
Summary
Researchers developed novel topological valley-locked waveguides using heterostructures. A C4 impurity acts as a switch, controlling light transmission for integrated photonic networks.
Area of Science:
- Topological photonics
- Condensed matter physics
- Materials science
Background:
- Heterostructures are key for designing valley-locked waveguides.
- Topological photonic crystals (VPCs) enable manipulation of light propagation.
- Valley-locking confines light to specific paths, crucial for photonic devices.
Purpose of the Study:
- To demonstrate extension of topological guided modes into trivial VPCs.
- To introduce a C4 impurity for controlling light transmission in topological valley-locked waveguides.
- To explore applications in on-chip integrated photonic networks.
Main Methods:
- Utilizing heterostructures to design valley-locked waveguides.
- Introducing a C4 impurity to induce intervalley scattering in Quantum Valley Spin Hall topological insulators.
- Demonstrating control of light transmission by rotating the C4 structure.
Main Results:
- Topological guided modes successfully extended from nontrivial to trivial VPCs.
- A C4 impurity enabled ON/OFF switching of valley-locked waveguides via rotation.
- Demonstrated potential for coding channels and energy concentrators.
Conclusions:
- The proposed C4 impurity acts as an effective switch for topological valley-locked waveguides.
- This design facilitates control over light wave transmission in photonic integrated circuits.
- The findings pave the way for advanced on-chip photonic networks.
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